The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 23, 1998
Filed:
Mar. 21, 1997
William R Creek, Fremont, CA (US);
Marvin L Wahl, Sunnyvale, CA (US);
Bryan L Clausen, Sr, San Jose, CA (US);
Mery Clausen, San Jose, CA (US);
Bryan Clausen, Jr, Menlo Park, CA (US);
The Board of Trustees of the Leland Stanford Junior University, Palo Alto, CA (US);
Abstract
A tracking system comprising multiple satellite units and a master unit for selectively and individually locating each satellite unit. Each satellite unit receives a search signal from the master unit and transmits a response signal to the master unit when the search signal contains a search identity code which matches a unique identity code of the satellite unit. The master unit has user controls for selecting any one of the satellite units to be located and a memory for storing the unique identity code of each satellite unit. The master unit also has an indicator circuit for indicating the strength of the response signal and a display and speaker for visually and audibly indicating the strength to a user. The master unit is programmed such that when the user selects one of satellite units to be located, the master unit transmits a search signal having a search identity code which matches the unique identity code of the selected satellite unit. The tracking system also preferably includes a passive re-radiating strip to be attached to an object to be tracked. The strip receives signals from the master unit at a fundamental frequency and re-radiates the signals at a multiple of the fundamental frequency. The master unit indicates the strength of the re-radiated signals to the user, enabling the user to locate the strip.